Effects of dietary phytosterols on growth performance, antioxidant status, and meat quality in Partridge Shank chickens

To investigate the effects of dietary phytosterols (PS) on growth performance, antioxidant status, and meat quality of Partridge Shank chickens, a total of 256 1-day-old male Partridge Shank chicks were randomly assigned into 4 dietary treatments, and each of them replicated 8 times with 8 chicks per replicate. Birds in the 4 treatments were fed a basal diet supplemented with 0 (Control group), 20, 40, and 80 mg/kg PS for 50 D, respectively. Dietary supplementation of PS quadratically increased average daily gain of chickens during the grower and overall periods, whereas linearly decreased the feed-to-gain ratio during the starter period. Compared with control group, a significant increase in average daily gain during the grower and overall periods was observed in chickens fed the basal diet supplemented with 40 mg/kg PS. Increasing PS addition linearly increased serum glutathione peroxidase (GSH-Px) activity at 21 and 50 D and hepatic GSH-Px and superoxide dismutase activities at 21 D, whereas linearly decreased malondialdehyde concentration of breast muscle at 50 D. Meanwhile, 40 mg/kg PS supplementation significantly increased serum GSH-Px activity, and hepatic superoxide dismutase and GSH-Px activities at 21 D as compared with the control. PS supplementation linearly and quadratically decreased drip loss (24 and 48 h postmortem) and luminance value (24 h postmortem) of breast muscle in broilers at 50 D, and there was statistical difference between the control and PS-supplemented group. In conclusion, PS supplementation can improve growth performance, antioxidant status, and meat quality of Partridge Shank chickens, with its optimum level in Partridge Shank chickens' diet being 40 mg/kg.